MS_DOS 2.11 (Was: DOS disks?

From: Fred Cisin <cisin_at_xenosoft.com>
Date: Tue Oct 27 17:28:30 1998

MS-DOS 2.11 was a very special version. It was the one where Microsoft
explicitly supported OEM modifications. Even the source code to IO.SYS
was obtainable! Each manufacturer that had something weird could make
their mods to it. For example: PC-DOS 3.20 was the first one to support
720K floppies. But LOTS of MS-DOS 2.11 variants support 720Ks. (NOT ALL
WITH THE SAME DISK FORMAT!!) Or the manufacturer could modify IO.SYS so
that pressing Ctrl+Alt+Meta+CokeBottle switches to power-saving "suspend
mode", etc.

Accordingly, 2.11 was usually tied to a given manufacturer. DG 2.11 was
not quite the same as Gavilan 2.11, etc. Typically, MODE.COM would be
heavily customized, and frequently IO.SYS would have a few differences.
For example, Gavilan 2.00, 2.10 or 2.11 all supported 3.5" disks, but
only 2.11 worked right. And 2.11K, 2.11L, etc. also supported double
sided disks.

If you CAN, try to find a copy of that 2.11 for your machine; the one
modified by the hardware manufacturer to work with the weirdities of your
hardware. If you choose to use one of the newer versions of DOS (6.2x is
the most reliable for a couple of reasons), at least keep a copy available
of the MODE.COM that was customized for your machine. You might need to
use SETVER, or disassemble and look for the code that goes:
MOV AH, 30h
INT 21h
CMP AX,

Using the newer version of DOS MIGHT cut you off from some of the
customizations, but hopefully MODE.COM may have most of the ones that you
need, such as MODE LCD , etc.

--
Fred Cisin                      cisin_at_xenosoft.com
XenoSoft                        http://www.xenosoft.com
2210 Sixth St.                  (510) 644-9366
Berkeley, CA 94710-2219
On Tue, 27 Oct 1998, Ward Donald Griffiths III wrote:
> Cameron Kaiser wrote:
> > 
> > Weeeeeeeell, I landed a Data General One laptop. Normally I eschew MS-DOS
> > based machines, simply because I'm a racist pig etc., but this one has an
> > interesting notebook mode and a built-in terminal program at 1200bps. Except
> > that the screen is harder to read than James Joyce, it seems like a winner
> > and it works great.
> > 
> > Question. Anyone know what version of DOS this uses? Does someone have any
> > boot disks out there, or at least have the system files available for
> > download? The drives are 3.5" DD, right?
> 
> Came as I recall with MS-DOS 2.11, should use anything up to 6.22,
> though of course it's tricky building a 720k 6.22.system disk.  3.3
> is probably your best bet, although I think there were some hardware
> specific utilities on the original material that might come in rather
> handy.  Nice machine -- the only DOS laptop to tempt me prior to the
> Zenith SuperSports.
> -- 
> Ward Griffiths <mailto:gram_at_cnct.com> <http://www.cnct.com/home/gram/>
> 
> WARNING:  The Attorney General has determined that Alcohol, Tobacco,
> and Firearms can be hazardous to your health -- and get away with it.

Received on Tue Oct 27 1998 - 17:28:30 GMT